style= background urlactive_mypanel Uncaught ReferenceError url is not defined

The error message suggests that the "url" variable is not defined in the code snippet you provided.

To fix this error, you need to define the "url" variable before using it in the code. The "url" variable should be a string representing the URL of the image you want to set as the background.

For example, if you want to set the background to the image "active_mypanel.jpg", you can define the "url" variable like this:

const url = "active_mypanel.jpg";

Then, you can use the "url" variable in the style attribute:

style={{ background: `url(${url})` }}

Make sure to replace "active_mypanel.jpg" with the actual URL or path to your desired image